Postless Hip Distraction Systems Decrease the Amount of Traction Force Needed to Obtain Adequate Hip Distraction Versus a Conventional Post Hip Distractor

Abstract

To directly compare hip distraction distance and traction force data for hip arthroscopy performed using a post-basedsystem versus a postless system. Adult patients undergoing primary hip arthroscopy for femoroacetabular impingement were prospectively enrolled. Before March 26, 2019, arthroscopy was performed using a post-based system. After this date, the senior author converted to using a postless system. Intraoperative traction force and fluoroscopic distraction distance were measured to calculate hip stiffness coefficients at holding traction (k-hold) and maximal traction (k-max). We used multivariable regression analysis to determine whether postless arthroscopy was predictive of lower stiffness coefficients when controlling for other relevant patient-specific factors. Hip arthroscopy was performed with a post-based system in 105 patients and with a postless system in 51. Mean holding traction force (67.5 ± 14.0 kilograms-force [kgf] vs 55.8 ± 15.3 kgf) and mean maximum traction force (96.0 ± 16.6 kgf vs 69.9 ± 14.1 kgf) were significantly lower in the postless group. On multivariable analysis, postless traction was an independentpredictor of decreased k-hold (β= -31.4; 95% confidence interval, -61.2 to -1.6) and decreased k-max (β= -90.4; 95% confidence interval, -127.8 to -53.1). Male sex, Beighton score of 0, and poor hamstring flexibility were also predictors of increased k-hold and k-max in the multivariable model. Postless traction systems decrease the amount of traction force required for adequate hip distraction for both maximal and holding traction forces when compared with post-based systems. Postless traction systems may help further reduce distraction-type neurologic injuries and pain after hip arthroscopy by lowering the traction force required to safely distract the hip. Level III, prospective cohort-historical control comparative study.